Molecular structure of blue laccase BP76, a unique termite suicidal defense weapon

Aging workers of the termite Neocapritermes taracua can defend their colony by sacrificing themselves by body rupture, mixing the externally stored blue laccase BP76 with hydroquinones to produce a sticky liquid rich in toxic benzoquinones. The study elucidates structure of BP76 isolated from N. taracua in its native form. The MS part of the study focused on characterization of the modification product of a metastable crosslink between K189 and C292, and to confirm suspected mutations. The remarkable stability of BP76 maintains its catalytic activity in solid state during the lifespan of N. taracua workers, providing old workers with an efficient defensive weapon to protect their colony. This work was supported by The Ministry of Education, Youth and Sports of the Czech Republic grant PHOTOMACHINES - Photosynthetic cell redesign for high yields of therapeutic peptides (CZ.02.01.01/00/22_008/0004624) and the Structural Mass Spectrometry Core Facility of CIISB, Instruct-CZ Centre, supported by MEYS CR (LM2018127) and the European Regional Development Fund Project, UP "CIISB" (No. CZ.02.1.01/0.0/0.0/18_046/0015974).